When more strength work stops helping
More time in the weight room wasn’t helping Kristine Kearns make the most of her running. During an earlier marathon block, she lifted heavily three times a week while running 35 to 40 miles. For her next half marathon, she cut back on strength work, built her running volume gradually and finished a hilly course in 1:46:50. The result points to a practical tradeoff: strength training can support running, but its value depends on whether an athlete can recover well enough to benefit from both.
Kearns describes herself as an anaerobic athlete: she enjoys fast running and strength sessions. But, as run coach Des Clarke explains, strength training can support durability, help prevent injuries and improve running economy. The challenge was fitting that work around the recovery her mileage demanded. Here's the thing: a session can be worthwhile in isolation and still make the rest of a training week harder to execute.
Building mileage while keeping strength work
Before beginning her second half marathon build, Kearns had been running at least twice a week for about eight months. She added a third running day before the plan began, then moved to four days a week once training started. Midweek runs grew from about four miles to five or six. That progression gave her more frequent exposure to running while avoiding a sudden jump in both frequency and distance.
That gradual approach matches Clarke’s advice for runners taking on longer distances. “If you want to get better at running, it is true that to a point, you need to run more,” she says. More running builds the aerobic capacity and durability needed to cover the distance. Clarke recommends adding volume incrementally and holding a given weekly total for two or three weeks before increasing it again. The point is to let the body adjust to a workload before layering on more; a plan that looks modest on paper can still be demanding when the athlete is adapting to it.
Recovery was part of the plan, too. Clarke suggests reducing mileage by around 10 to 20 percent for a deload week every three weeks or so, giving the body a chance to absorb training. Kearns’s schedule included easier weeks as she built up her mileage. A lighter week also creates room to notice how the accumulated work is landing, rather than treating every week as a test of how much more an athlete can tolerate.
She also trimmed her gym schedule from three sessions to one or two each week. Instead of spending an hour or more lifting each time, she kept sessions to 30 to 45 minutes and split her usual routine across two days. That change preserved a place for strength work while making its demands easier to fit around running. It’s a measured adjustment, and more useful than assuming that every runner needs to choose between lifting and mileage.
More recovery, better workouts
During marathon training, Kearns had spent more than four hours a week lifting alongside 35 to 40 miles of running. Cutting back on gym time made it easier to take recovery seriously. By the time her Wednesday track workout came around, she felt ready for intervals, and the two-mile warm-up no longer felt like a slog. That’s a meaningful shift in training quality: the workout depends on arriving with enough energy to run it as intended, not merely checking it off the calendar.
She noticed a difference beyond training, too. On recovery days, she felt more focused and upbeat at work and had more energy for social plans. Feeling refreshed made it easier to look forward to her next run. And this is the part most people overlook: recovery has consequences outside the next workout, and those daily signs can help an athlete judge whether a schedule is sustainable.
A faster finish on a hilly course
Kearns initially expected to aim for a sub-two-hour half marathon. After a coach suggested she could run faster, she reset her target to roughly 1:45 to 1:50. She crossed the line in 1:46:50, just seconds off her personal best, which she had set on a much flatter course. The comparison is useful because the finish came on a hilly route, though one race can’t isolate which training change accounted for the result.
Her pacing was a particular bright spot. She started with the 1:50 pacer, then moved ahead after three or four miles, averaging 8:10 per mile despite the hills. The result suggests her schedule worked because it balanced added mileage with enough recovery to run the workouts well. For runners increasing distance, the useful lesson is to make room for running by managing strength volume, then give each new training load time to settle. A faster time isn’t guaranteed by cutting gym sessions; the more defensible takeaway is that training quality depends on how its parts fit together.
What the adjustment means for other runners
This is more significant than it looks: Kearns didn’t abandon strength training or chase mileage without limits. She adjusted both around the demands of the event she was preparing for, then paid attention to whether she could complete key runs feeling ready. If you're working in this space, that’s a more transferable model than copying her weekly totals, which reflect her own starting point and schedule.
The numbers here are underwhelming as proof of cause and effect: one runner’s race can’t establish that fewer gym sessions will make other runners faster. But the account does show why training plans need to account for fatigue across the whole week. For an athlete who enjoys lifting, the choice may be to shorten sessions, reduce their frequency, or distribute the work differently while mileage rises. The right adjustment is the one that leaves enough capacity for consistent running and recovery.
Keep the strength work that serves your goals. Make the running increase gradual. Then judge the plan by more than the total miles or the weight lifted: whether workouts are improving, whether recovery feels adequate, and whether the schedule remains livable. A sustainable routine. That said, Kearns’s experience offers a clear reminder that adding more training is only useful when the body has room to absorb it.
Kristine Kearns, a writer and avid runner, joined Runner’s World and Bicycling in July 2024. She previously coached high school girls cross country and currently competes in seasonal races, with more than six years of distance training and an affinity for weightlifting. You can find her wearing purple, baking cupcakes, and visiting her local farmers market.
